1. Field of the Invention
The present invention relates to a radio communication apparatus, a radio communication method, a program, and a radio communication system.
2. Description of the Related Art
Nowadays, radio LAN (Local Area Networks) standards such as IEEE802.11a and IEEE802.11b have been developed. In such radio LAN standards, an infrastructure mode in which an access point (base station) arbitrates access timing for a plurality of radio communication apparatuses and an ad hoc mode in which access timing is decided between radio communication apparatuses are mentioned.
The infrastructure mode via an access point has a disadvantage that throughput is lower than the ad hoc mode, but has an advantage that subordinate radio communication apparatuses can connect to a wire LAN or the Internet. The ad hoc mode has higher throughput because radio communication apparatuses directly communicate with each other so that there is no overhead due to an access point relay, but has a disadvantage that a wire LAN or the Internet may not be connected.
The TDLS (Tunneled Direct. Link Setup) method is defined in IEEE802.11z as a method that can make use of advantages of each mode. According to the TDLS method, radio communication apparatuses can directly communicate by setting up a direct link (direct communication link) while maintaining the infrastructure mode. Also in these days, PPSM (Peer Power Save Mode) for radio communication apparatuses to enter the power save mode even after the direct, link being set up. For example, Japanese Patent Application Laid-Open No. 2006-93945 describes content of a radio communication apparatus notifying a base station under whose command the radio communication apparatus is of transition into power save mode.